Two-component adhesive-, sealing- or coating compositions are already known for a long time. They consist of a separately packed resin component having reactive groups, e.g. epoxy groups, and a curing agent. Both components are mixed just before use and the mixture is applied immediatedly after (within the "period of exposure") onto the corresponding substrate where it is curing.
An essential drawback of these two-component systems is the fact that the mixing of both components is being carried out by the user and that an inaccurate mixing ratio of both components is leading to a deterioration of the strength of the cured adhesive-, sealing- or coating composition.
In case that the resin component contains reactive groups which are causing rapid curing at the contact with a curing agent, but are also slowly curing with water to completion, e.g. ambient moisture, then it is not crucial to operate with an inaccurate mixture having a deficiency of the curing agent, because a gradual curing to completion of the resin component is taking place anyway.
However, it is more critical, when during use more curing agent is added than necessary for curing to completion of the resin component. In this case the surplus of curing agent remains after complete curing of the resin component as a "foreign ingredient" within the mixture, thus, causing a dramatic deterioration of the mechanic properties of the cured composition. Corresponding compositions that are displaying very good mechanic properties when the mixing ratio of the resin component and the curing agent, issued by the producer, is being well respected, show completely unsatisfactory values, in the case that the user is adding bigger quantities of curing agent during the preparation of the mixture than necessary for complete curing.
Furthermore, it is important for known two-component adhesive-, sealing- or coating compositions that a uniform and homogeneous mixing of the resin component with the curing agent is being carried out for use, because otherwise the cured adhesive-, sealing- or coating composition also has areas with a too high or too low content of curing agent, even if the correct mixing ratio of resin component and curing agent is being used which is leading to the problems already described concerning the diminution of mechanic properties of the cured composition.
From the above-mentioned reasons, in recent years one-component adhesive-, sealing- or coating-compositions have been more and more accepted. These one-component adhesive-, sealing- or coating compositions have a resin component with reactive groups which are curing through the effect of atmospheric moisture at ambient temperature, or these one-component compositions are containing an additional inactivated curing agent which is added homogeneously to the resin component by the manufacturer respecting the accurate mixing ratio. The corresponding one-component products are storable at room temperature and are curing only when the adhesive area is being heated to the on-set temperature of the curing agent.
A heating of the adhesive area, however, is undesirable or even impossible in many applications, and therefore for these applications only the use of those one-component systems is possible that are exclusively curing after the application through the effect of water, for example by ambient atmospheric moisture.
These systems, however, have the drawback that long curing times are necessary for thorough curing and immediately after joining the substrates to be glued, the adhesion is that weak that a fixation of the parts to be glued is absolutely necessary. This is highly undesirable in many applications, for example in the manufacturing of motor vehicles, like automobiles, buses, shipbuilding as well as building commerce, e.g. home building, for example if the corresponding one-component adhesive-, sealing- or coating compositions are used to glue wind-shields or to glue home windows.
A further drawback is that the speed of the curing depends on the available atmospheric moisture and that with cold ambient temperatures and little atmospheric moisture it can take several weeks until complete curing is being achieved.
Since the curing is taking place from the exterior to the interior through the effect of atmospheric moisture, it is further dependent on the diffusion of the penetrating water in the adhesive layer and thick adhesive layers are curing extremely slowly, and, furthermore, also those adhesive layers are curing slowly that are linking large surfaces of substrates, because the interior areas of the surfaces that are to be glued impede strongly the penetration of humidity.
Due to these difficulties, known one-component adhesive-, sealing- or coating compositions for many applications and particular environmental conditions have been completely unsuitable so far and the two-component systems have to be used despite the above-mentioned drawbacks.
The subject of the present invention is to develop a two-component adhesive-, sealing- or coating composition in which both components are packed separately and which are storable, whereby when the components get in touch with each other, the mixing ratio between the resin component and the curing agent is not crucial because the resin component is curing also in the absence of curing agent through atmospheric moisture and because the curing agent is curing on its own to a solid composition due to the effect of atmospheric moisture, or because a possible surplus of the curing agent is steadily evaporating.